This invention relates to a liquid crystal display device, in particular, to a liquid crystal display device having a high aperture ratio.
The conventional liquid crystal display device comprises a scanning line for supplying a scanning signal, a data line for supplying a data signal, a common electrode for supplying a reference potential, a pixel electrode corresponding to a pixel and a thin-film transistor (TFT). A pixel is selected by the scanning signal supplied via the scanning signal line. The data signal supplied via the data line is retained to the selected pixel.
However, a leak electric field is generated between the data line and the pixel electrode in accordance with a voltage supplied to the date line in the conventional liquid crystal display device. This leak electric field gives an adverse influence to a liquid crystal layer.
For example, an aligning condition of liquid crystal molecules close to the data line is disturbed by the leak electric field due to the data line in a normal black mode. As a result, although a black must be naturally displayed, a white or a gray is displayed. That is, so called "cross talk" occurs. Therefore, a light shield area must be sufficiently provided close to the data line. As a result, the aperture ratio is lowered.